Mixed refrigerant composition and heat pump including same

Abstract

Disclosed are a mixed refrigerant composition and a heat pump including the same. A mixed refrigerant composition according to an exemplary embodiment may include a carbon dioxide (carbon dioxide, R-744), a 2, 3, 3, 3-tetrafluoropropene (2, 3, 3, 3-tetrafluoropropene, R-1234yfXA), and a 1, 1-difluoroethane (1, 1-difluoroethane, R-152a), and may be used in a refrigerant system for a vehicle. The content of carbon dioxide (R-744) may be 1 wt% to 10 wt% of the total weight of the mixed refrigerant composition, the content of 2, 3, 3, 3-tetrafluoropropene (R-1234yf) may be 65 wt% to 95 wt% of the total weight of the mixed refrigerant composition, and the content of 1, 1-difluoroethane (R-152a) may be 1 wt% to 30 wt% of the total weight of the mixed refrigerant composition. The boiling point of the mixed refrigerant composition at 1 atm may be in the range of-65 DEG C to-30 DEG C. The mixed refrigerant composition and the heat pump including the same can inhibit the ozone layer from being damaged and other environmental pollution.

Description

Technical Field

[0001] The present invention relates to a composition comprising a refrigerant and a heat pump comprising the same. Background Art

[0002] Refrigerant refers to a substance used to remove heat in heat pumps used in air conditioners, refrigerators, cooling towers, etc. Examples of refrigerants include natural refrigerants, chlorofluorocarbon (CFC) refrigerants, hydrochlorofluorocarbon (HCFC) refrigerants, hydrofluorocarbon (HFC) refrigerants, and hydrofluoroolefin (HFO) refrigerants.

[0003] Recently, the types of heat pumps used indoors and outdoors have diversified, and miniaturized heat pumps are required due to the development of electric vehicles, etc. In addition, since refrigerants containing chlorine (Cl) may damage the ozone layer, etc., attempts are being made to develop refrigerants that do not contain chlorine atoms.

[0004] For example, 2,3,3,3-tetrafluoropropane (R-1234yf), as a hydrofluoroolefin refrigerant, does not contain chlorine atoms, and therefore has a low global warming potential (GWP), and is widely used as a refrigerant for car air conditioners.

[0005] However, since 2,3,3,3-tetrafluoropropene has a low coefficient of performance (COP), an additional heat pump is required when it is used as a refrigerant for a car air conditioner, and thus there is a problem of low energy efficiency.

[0006] Therefore, it is necessary to develop a refrigerant or a refrigerant combination that can suppress environmental pollution and has a high coefficient of performance. Summary of the invention

[0007] Technical issues

[0008] An object according to an exemplary embodiment is to provide a mixed refrigerant composition having improved environmental performance.

[0009] An object according to an exemplary embodiment is to provide a heat pump including the above-mentioned mixed refrigerant composition and having improved refrigeration performance.

[0010] Technical Solution

[0011] According to an embodiment of the present disclosure, the mixed refrigerant composition comprises carbon dioxide (R-744), 2,3,3,3-tetrafluoropropene (R-1234yf) and 1,1-difluoroethane (R-152a). The content of the carbon dioxide (R-744) is 1% to 10% by weight of the total weight of the mixed refrigerant composition, the content of the 2,3,3,3-tetrafluoropropene (R-1234yf) is 65% to 95% by weight of the total weight of the mixed refrigerant composition, and the content of the 1,1-difluoroethane (R-152a) is 1% to 30% by weight of the total weight of the mixed refrigerant composition. The boiling point of the mixed refrigerant composition at 1 atm is -65°C to -30°C.

[0012] The mixed refrigerant composition according to an exemplary embodiment may be composed of the above-mentioned carbon dioxide (R-744), the above-mentioned 2,3,3,3-tetrafluoropropylene (R-1234yf), and the above-mentioned 1,1-difluoroethane (R-152a).

[0013] According to an exemplary embodiment, the content of the 1,1-difluoroethane (R-152a) may be 13 wt % to 25 wt % based on the total weight of the mixed refrigerant composition.

[0014] According to an exemplary embodiment, the content of the 1,1-difluoroethane (R-152a) may be 18 wt % to 23 wt % based on the total weight of the mixed refrigerant composition.

[0015] According to an exemplary embodiment, a ratio of the content of the 2,3,3,3-tetrafluoropropylene (R-1234yf) to the carbon dioxide (R-744) may be 6 to 95 in the total weight of the mixed refrigerant composition.

[0016] According to an exemplary embodiment, the ratio of the content of 1,1-difluoroethane (R-152a) to the carbon dioxide (R-744) may be 0.5 to 30 in the total weight of the mixed refrigerant composition.

[0017] According to an exemplary embodiment, a ratio of the content of the 2,3,3,3-tetrafluoropropylene (R-1234yf) to the content of the 1,1-difluoroethane (R-152a) may be 2 to 19 in the total weight of the mixed refrigerant composition.

[0018] According to an exemplary embodiment, the critical temperature of the mixed refrigerant composition may be 90°C to 100°C.

[0019] According to an exemplary embodiment, the critical pressure of the mixed refrigerant composition may be 30 bar to 51 bar.

[0020] According to an exemplary embodiment, the temperature glide of the mixed refrigerant composition at a pressure of 1.5 bar may be 3° C. to 29° C.

[0021] According to an exemplary embodiment, the temperature glide of the mixed refrigerant composition at a pressure of 15 bar may be 2° C. to 23° C.

[0022] According to an exemplary embodiment, the latent heat of the mixed refrigerant composition at -25°C may be 150 kJ / kg to 250 kJ / kg.

[0023] According to an exemplary embodiment, the global warming potential (GWP) of the mixed refrigerant composition may be 1 to 40.

[0024] A heat pump according to an embodiment of the present disclosure includes the mixed refrigerant composition.

[0025] Technical Effects

[0026] According to the mixed refrigerant composition of the exemplary embodiment, since the refrigerant included in the mixed refrigerant composition may not contain chlorine atoms (Cl), environmental pollution such as the destruction of the ozone layer may be suppressed.

[0027] According to the mixed refrigerant composition of the exemplary embodiment, the ambient temperature can be effectively lowered even at low temperatures as the refrigerant composition is vaporized from liquid to gas.

[0028] In addition, the mixed refrigerant composition does not undergo a phase change to a supercritical state during operation of a cooling machine such as an air conditioner, so that the condensing pressure of the compressor may not be reduced, and the coefficient of performance of a heat pump including the mixed refrigerant composition may be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 and Figure 2 2 are schematic diagrams respectively illustrating flows of a mixed refrigerant for heat exchange in a cooling mode or a heating mode of a heat exchanger according to exemplary embodiments. DETAILED DESCRIPTION

[0030] According to an exemplary embodiment, a mixed refrigerant composition including carbon dioxide (R-744), 2,3,3,3-tetrafluoropropene (R-1234yf) and 1,1-difluoroethane (R-152a) and a heat pump including the mixed refrigerant composition are provided.

[0031] The present disclosure is described in detail below, but this is merely an example, and the present disclosure is not limited to the specific embodiments described exemplarily.

[0032] According to an exemplary embodiment, the refrigerant included in the mixed refrigerant composition may be a refrigerant that does not contain chlorine atoms (Cl). As refrigerants that do not contain chlorine atoms (Cl), for example, natural refrigerants, hydrofluorocarbon (HFC) refrigerants, hydrofluoroolefin (HFO) refrigerants, etc. can be cited.

[0033] The natural refrigerant is a substance naturally existing on earth, rather than an artificial compound. The natural refrigerant may include, for example, at least one of ammonia (R-717), carbon dioxide (R-744), propane (R-290), propylene (R-1270) and butane (R-600a).

[0034] The hydrofluorocarbon (HFC) refrigerant is a refrigerant composed of hydrogen atoms (H), fluorine atoms (F), and carbon atoms (C). The above-mentioned hydrofluorocarbon (HFC) refrigerants may include, for example, at least one of difluoromethane (R-32), trifluoroiodomethane (R-13I1), 1,1-difluoroethane (R-152a), pentafluoroethane (R-125), 1,1,1-trifluoroethane (R-143a), trifluoromethane (R-23), fluoroethane (R-161), 1,1,1,2,3,3,3-heptafluoropropane (R-227ea), 1,1,1,2,3,3-hexafluoropropane (R-236ea), 1,1,1,3,3,3-hexafluoropropane (R-236fa), 1,1,1,3,3-pentafluoropropane (R-245fa) and 1,1,1,3,3-pentafluorobutane (R-365mfc).

[0035] The above-mentioned hydrofluoroolefin (HFO) refrigerant is a refrigerant composed of hydrogen atoms (H), fluorine atoms (F) and carbon atoms (C) and having at least one double bond between the above-mentioned carbon atoms. The above-mentioned hydrofluoroolefin (HFO) refrigerant may include, for example, at least one of 1,1,2-trifluoroethylene (R-1123), 2,3,3,3-tetrafluoropropylene (R-1234yf), 1,3,3,3-tetrafluoropropylene (R-1234ze), 1,2,3,3-tetrafluoropropylene (R-1234ye), 3,3,3-trifluoropropylene (R-1243zf), 1,1-difluoroethylene (R-1132a) and 1,2,3,3,3-pentafluoropropylene (R-1225ye).

[0036] The mixed refrigerant composition according to an embodiment of the present disclosure includes carbon dioxide (R-744), 2,3,3,3-tetrafluoropropylene (R-1234yf) and 1,1-difluoroethane (R-152a). The carbon dioxide (R-744), 2,3,3,3-tetrafluoropropylene (R-1234yf) and 1,1-difluoroethane (R-152a) contained in the mixed refrigerant composition do not contain chlorine atoms (Cl).

[0037] The carbon dioxide (R-744) is a natural refrigerant with an ozone depletion potential (ODP) of 0 and a global warming potential (GWP) of 1. In addition, the carbon dioxide (R-744) may not be corrosive, toxic, or explosive. The inclusion of the carbon dioxide (R-744) in the mixed refrigerant composition may improve the environmental friendliness and stability of the mixed refrigerant composition.

[0038] The 2,3,3,3-tetrafluoropropene (R-1234yf) is a hydrofluoroolefin (HFO) refrigerant having an ozone depletion potential (ODP) of 0 and a global warming potential (GWP) of 4 or less. In addition, the R-1234yf may have high thermal stability and high latent heat of evaporation. The inclusion of the 2,3,3,3-tetrafluoropropene (R-1234yf) in the mixed refrigerant composition may improve the environmental friendliness, thermal stability and refrigeration capacity of the mixed refrigerant composition.

[0039] The above-mentioned 1,1-difluoroethane (R-152a) is a hydrofluorocarbon (HFC) refrigerant, and the ozone depletion potential (ODP) is 0, and the global warming potential (GWP) is less than 150. In addition, the above-mentioned 1,1-difluoroethane (R-152a) can have a small molecular weight and saturation density. The above-mentioned 1,1-difluoroethane (R-152a) is included in the above-mentioned mixed refrigerant composition, and the environmental protection of the above-mentioned mixed refrigerant composition can be improved. In addition, since the saturation density and the discharge pressure from the compressor can be lower, the enthalpy change under the same compression ratio (pressure ratio) can be increased. Therefore, the refrigeration capacity of the mixed refrigerant composition can be improved.

[0040] In some embodiments, the mixed refrigerant composition may not contain any refrigerants other than carbon dioxide (R-744), 2,3,3,3-tetrafluoropropylene (R-1234yf) and 1,1-difluoroethane (R-152a). For example, the mixed refrigerant composition may not contain additional hydrofluorocarbon (HFC) refrigerants such as difluoromethane (R-32) with high global warming potential. Therefore, the environmental friendliness of the mixed refrigerant composition can be improved. For example, the mixed refrigerant composition may not contain additional hydrofluoroolefin (HFO) refrigerants such as 1,1-difluoroethylene (R-1132a) with toxicity. Therefore, safety can be improved even if some mixed refrigerant compositions flow out of the heat pump.

[0041] For example, the mixed refrigerant composition may consist of only carbon dioxide (R-744), 2,3,3,3-tetrafluoropropylene (R-1234yf) and 1,1-difluoroethane (R-152a). Therefore, it is possible to prevent the decrease in thermal stability and / or chemical stability due to the mixing of refrigerants with low thermal stability and / or chemical stability. In addition, it is possible to prevent the increase in condensation temperature due to the mixing of refrigerants with low vapor pressure, or the decrease in refrigeration capacity due to the mixing of refrigerants with low latent heat of evaporation.

[0042] According to exemplary embodiments, the content of the above-mentioned carbon dioxide (R-744) can be 1 wt % to 10 wt %, 1 wt % to 8 wt %, or 1 wt % to 6 wt %, 1 wt % to 5 wt % of the gross weight of the above-mentioned mixed refrigerant composition. When the content of the above-mentioned carbon dioxide (R-744) is lower than 1 wt % of the gross weight of the above-mentioned mixed refrigerant composition, the global warming potential (GWP) of the mixed refrigerant composition can increase, thereby can reduce environmental protection. When the content of the above-mentioned carbon dioxide (R-744) exceeds 10 wt % of the gross weight of the above-mentioned mixed refrigerant composition, the refrigeration capacity of the mixed refrigerant composition can decline. Therefore the refrigeration characteristics of the mixed refrigerant composition can decline. In the case of the above-mentioned content range, the global warming potential (GWP) of the mixed refrigerant composition can be reduced but the refrigeration performance is not reduced. Therefore the environmental protection and refrigeration characteristics of the mixed refrigerant composition can be improved.

[0043] In some embodiments, the content of the carbon dioxide (R-744) can be 1.5 wt % to 5 wt %, 2 wt % to 5 wt %, 3 wt % to 5 wt %, or 4 wt % to 5 wt %, or 4.5 wt % to 5 wt % of the total weight of the mixed refrigerant composition. In the case of the above content range, the environmental protection and refrigeration characteristics of the mixed refrigerant composition can be further improved.

[0044] According to an exemplary embodiment, the content of the above-mentioned 2,3,3,3-tetrafluoropropylene (R-1234yf) can be 65% to 95% by weight, 70% to 95% by weight, or 70% to 90% by weight, or 75% to 90% by weight of the total weight of the above-mentioned mixed refrigerant composition. When the content of the above-mentioned 2,3,3,3-tetrafluoropropylene (R-1234yf) is less than 65% by weight of the total weight of the above-mentioned mixed refrigerant composition, the content of 1,1-difluoroethane (R-152a) can be increased, thereby reducing thermal stability. In addition, the content of carbon dioxide (R-744) can be increased, thereby reducing refrigeration capacity. When the content of the above-mentioned 2,3,3,3-tetrafluoropropylene (R-1234yf) exceeds 95% by weight of the total weight of the above-mentioned mixed refrigerant composition, the content of 1,1-difluoroethane (R-152a) can be reduced, thereby reducing refrigeration capacity. In the case of the above content range, the thermal stability, refrigeration capacity and environmental friendliness of the mixed refrigerant composition can be improved.

[0045] In some embodiments, the content of 2,3,3,3-tetrafluoropropene (R-1234yf) can be 75 wt% to 90 wt%, 75 wt% to 89 wt%, 75 wt% to 88 wt%, or 75 wt% to 87 wt%, or 75 wt% to 85 wt% of the total weight of the mixed refrigerant composition. In the case of the above content range, the thermal stability and refrigeration capacity of the mixed refrigerant composition can be further improved.

[0046] According to exemplary embodiments, the content of the above-mentioned 1,1-difluoroethane (R-152a) can be 1 weight % to 30 weight %, 3 weight % to 30 weight %, or 5 weight % to 30 weight % of the total weight of the above-mentioned mixed refrigerant composition. When the content of the above-mentioned 1,1-difluoroethane (R-152a) is less than 1 weight % of the total weight of the above-mentioned mixed refrigerant composition, the refrigeration capacity can decrease. When the content of the above-mentioned 1,1-difluoroethane (R-152a) exceeds 30 weight % of the total weight of the above-mentioned mixed refrigerant composition, the global warming potential (GWP) value can increase, thereby reducing the environmental protection of the above-mentioned mixed refrigerant composition. In the case of the above-mentioned range, the environmental protection of the mixed refrigerant composition is improved and the refrigeration performance will also be improved.

[0047] In some embodiments, the content of the 1,1-difluoroethane (R-152a) can be 10% to 30% by weight, 10% to 25% by weight, 13% to 25% by weight, 15% to 25% by weight, or 15% to 23% by weight, or 18% to 23% by weight of the total weight of the mixed refrigerant composition. In the case of the above content range, the environmental protection of the mixed refrigerant composition is improved, the refrigeration capacity can also be further improved, and the latent heat of evaporation of the mixed refrigerant composition can be further increased. Therefore, the refrigeration capacity can be further improved.

[0048] In some embodiments, in the total weight of the mixed refrigerant composition, the ratio of the content of the 2,3,3,3-tetrafluoropropene (R-1234yf) to the content of the carbon dioxide (R-744) may be 6 to 95, 6 to 90, 10 to 85, 10 to 80 or 13 to 80. Within the above range, the thermal stability, environmental protection and refrigeration capacity of the mixed refrigerant composition can be improved.

[0049] In one embodiment, the ratio of the content of the 2,3,3,3-tetrafluoropropene (R-1234yf) to the content of the carbon dioxide (R-744) in the total weight of the mixed refrigerant composition may be 13 to 60, 13 to 45, 13 to 40, 13 to 35, 13 to 30, or 13 to 25, or 13 to 20, or 13 to 18. Within the above range, the thermal stability, environmental protection and refrigeration capacity of the mixed refrigerant composition can be further improved.

[0050] In some embodiments, the ratio of the content of the 1,1-difluoroethane (R-152a) to the content of the carbon dioxide (R-744) in the total weight of the mixed refrigerant composition may be 0.5 to 30, 1 to 25, 1 to 20, or 1 to 15. Within the above ranges, the refrigeration capacity of the mixed refrigerant composition can be increased.

[0051] In one embodiment, the ratio of the content of the 1,1-difluoroethane (R-152a) to the content of the carbon dioxide (R-744) in the total weight of the mixed refrigerant composition may be 1 to 15, 1 to 10, 1 to 7 or 1 to 6. Within the above range, the refrigeration capacity of the mixed refrigerant composition can be further improved.

[0052] In some embodiments, the ratio of the content of 2,3,3,3-tetrafluoropropylene (R-1234yf) to the content of 1,1-difluoroethane (R-152a) in the total weight of the mixed refrigerant composition may be 2 to 19, 2 to 18, 2 to 15, 2 to 10, 3 to 10, 3 to 9 or 3 to 6. Within the above ranges, thermal stability and refrigeration capacity can be improved.

[0053] In one embodiment, the ratio of the content of the 2,3,3,3-tetrafluoropropylene (R-1234yf) to the content of the 1,1-difluoroethane (R-152a) in the total weight of the mixed refrigerant composition may be 3.5 to 6, 3.5 to 5.5, 3.5 to 5.4, 3.5 to 5, or 3.5 to 4. Within the above range, the thermal stability and refrigeration capacity of the mixed refrigerant composition can be further improved.

[0054] According to exemplary embodiments, the boiling point of the mixed refrigerant composition at 1 atm may be -65°C to -30°C, -60°C to -30°C, -55°C to -34°C, or -55°C to -40°C.

[0055] In case the boiling point of the mixed refrigerant composition is lower than -65°C, the condensation pressure at the condensation temperature of the mixed refrigerant composition may increase. Therefore, the energy consumed in the refrigeration cycle may increase, and the efficiency of the refrigerant may be reduced.

[0056] When the boiling point of the mixed refrigerant composition exceeds -30°C, the specific volume at the condensation temperature of the mixed refrigerant composition may increase. Therefore, the amount of the mixed refrigerant composition required to improve the refrigeration capacity increases, and thus the volume of the air conditioner may increase.

[0057] In some embodiments, the boiling point of the mixed refrigerant composition at 1 atm may be -55°C to -45°C, -53°C to -45°C, or -53°C to -48°C. In the case of the boiling point range of the mixed refrigerant composition, the condensing pressure does not increase and the specific volume can be reduced. Therefore, the amount of the mixed refrigerant composition can be reduced and the refrigeration capacity of the refrigerant can be improved.

[0058] In some embodiments, the critical temperature of the mixed refrigerant composition may be 90° C. to 100° C., 95° C. to 100° C., 97° C. to 100° C., or 97° C. to 99° C. The critical temperature refers to the highest temperature at which a specific substance can exist in a liquid state. If the critical temperature of the refrigerant is low, it may be difficult to achieve the liquefaction of the refrigerant in the condensation process in the refrigeration cycle.

[0059] In the case of the critical temperature range, the mixed refrigerant composition may not become a supercritical fluid state in the refrigeration cycle. Therefore, it is possible to prevent a part of the mixed refrigerant composition from becoming a supercritical fluid state without liquefaction, thereby improving the refrigeration capacity.

[0060] In some embodiments, the critical pressure of the mixed refrigerant composition may be 30 bar to 51 bar, 30 bar to 50 bar, 35 bar to 50 bar, 35 bar to 45 bar, 39 bar to 45 bar, or 40 bar to 45 bar. Critical pressure refers to the maximum pressure at which a specific substance can exist in a liquid state. When the critical pressure of the refrigerant is high, the refrigerant may be difficult to liquefy in the refrigeration cycle.

[0061] In the case of the critical pressure range, the mixed refrigerant composition may not become a supercritical fluid state in the refrigeration cycle, so that a part of the mixed refrigerant composition may be prevented from not being liquefied, thereby improving the refrigeration capacity.

[0062] In some embodiments, the temperature glide of the mixed refrigerant composition at a pressure of 1.5 bar may be 3°C to 29°C, 3°C to 28°C, 8°C to 27°C, 10°C to 26°C, 11°C to 26°C, 11°C to 25°C, 11°C to 20°C, or 15°C to 20°C. In the case of the above temperature gradient range, even if the mixed refrigerant leaks, the separation of components will not occur. Therefore, even if the same volume of heat pump is used, the use capacity of the mixed refrigerant composition can be increased.

[0063] In some embodiments, the temperature glide of the mixed refrigerant composition at a pressure of 15 bar may be 2°C to 23°C, 2°C to 13°C, 4°C to 13°C, 4.5°C to 13°C, 5°C to 13°C, 6.5°C to 13°C, 9°C to 13°C, or 11°C to 13°C. In the case of the above temperature gradient range, the mixed refrigerant composition will not separate components even if it is used in a heat pump. Therefore, the heat transfer efficiency of the refrigerant can be improved.

[0064] In some embodiments, the latent heat at -25°C may be 150 kJ / kg to 250 kJ / kg, 180 kJ / kg to 250 kJ / kg, 180 kJ / kg to 230 kJ / kg, 180 kJ / kg to 220 kJ / kg, 190 kJ / kg to 220 kJ / kg, 195 kJ / kg to 220 kJ / kg, 200 kJ / kg to 215 kJ / kg, or 205 kJ / kg to 215 kJ / kg.

[0065] In the case of the above latent heat range, the heat released or absorbed during the phase change of the mixed refrigerant composition may be sufficient, and thus the thermal efficiency of the above mixed refrigerant composition may be improved.

[0066] In some embodiments, the global warming potential (GWP) of the mixed refrigerant composition may be 1-40, 1-30, 5-30, 10-30, 10-28, 15-28 or 19-28.

[0067] The global warming potential (GWP) is based on the 2 ) is a numerical value of the impact on global warming caused by releasing 1 kg of any chemical substance into the Earth's troposphere over a certain period of time (for example, 100 years) converted from a reference substance.

[0068] In the case of the above-mentioned global warming potential range, environmental pollution caused by the use and treatment of the mixed refrigerant composition can be suppressed and the refrigeration capacity can be improved.

[0069] In some embodiments, the ozone depletion potential (ODP) of the mixed refrigerant composition may be zero.

[0070] Ozone depletion potential (ODP) is a numerical value that converts the degree of impact of any chemical substance on the ozone layer depletion, assuming that the ozone layer depletion impact of trichlorofluoromethane (CFC-11) is 1.

[0071] The ozone depletion potential (ODP) is 0, so that environmental pollution caused by the use and treatment of the mixed refrigerant composition can be suppressed.

[0072] In some embodiments, the mixed refrigerant composition may be non-flammable. For example, it may be A2L grade in the refrigerant safety group classification of the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). Therefore, the stability of the heat pump during operation and leakage can be improved.

[0073] According to an exemplary embodiment, a heat pump includes the mixed refrigerant composition, so that the environmental friendliness and stability of the heat pump are improved and the refrigeration performance can also be improved.

[0074] The heat pump may include a compressor, a condenser, an expansion valve and an evaporator. In the compressor, the mixed refrigerant composition may be compressed into a high-temperature and high-pressure state, and in the expansion valve, the mixed refrigerant composition may be expanded into a low-temperature and low-pressure state.

[0075] For example, inside the heat pump, the mixed refrigerant composition may release heat or absorb heat during the cycle of the compressor, condenser, expansion valve and evaporator. The mixed refrigerant composition may maintain a high temperature and high pressure gas state in the compressor. The mixed refrigerant composition may release heat and liquefy into a liquid state in the condenser. The mixed refrigerant composition may maintain a low temperature and low pressure liquid state or a mixed state of liquid and gas in the expansion valve. The mixed refrigerant composition may absorb heat and vaporize into a gas state in the evaporator.

[0076] In some embodiments, the heat pump may include oil. For example, the oil may include paraffin, cycloalkane, aromatic hydrocarbon, polyester (POE), polyol ester (POE), mineral oil (mineral), alkylbenzene (AB), polyalkylene glycol (PAG), polyvinyl ether (PVE), etc. Therefore, friction and wear of the heat pump can be prevented.

[0077] In some embodiments, the coefficient of performance (COP) of the heat pump may be 1 to 10. The coefficient of performance (COP) refers to the ratio of the heat effectively obtained to the work input when the heat pump is running.

[0078] By using the above refrigerant, a high-efficiency heat pump having a coefficient of performance within the above range can be provided.

[0079] Preferred embodiments are given below to help understand the present application, but these embodiments are merely illustrative of the present application and do not limit the appended claims. It is obvious to a person skilled in the art that various changes and modifications can be made to the embodiments within the scope of the present application and the technical concept, and it is natural that these deformations and modifications belong to the appended claims.

[0080] Examples and Comparative Examples

[0081] (1) Mixed refrigerant composition

[0082] A mixed refrigerant composition having the components and contents (weight %) shown in Table 1 below was prepared.

[0083] The boiling point, critical temperature, critical pressure, temperature gradient at 1.5 bar and 15 bar, and latent heat at -25°C of the prepared mixed refrigerant composition were measured. The boiling point, critical temperature, critical pressure, temperature gradient at 1.5 bar and 15 bar, and latent heat at -25°C of the measured mixed refrigerant composition are shown in the following Table 1.

[0084] The boiling point, critical temperature, critical pressure, temperature gradient and latent heat of the mixed refrigerant composition were measured using REFPROP (Ver 10, NIST).

[0085]

Table 1

[0086]

[0087] The specific components recorded in Table 1 are as follows:

[0088] R-744:Carbon dioxide

[0089] R-1234yf: 2,3,3,3-tetrafluoropropane R-152a: 1,1-difluoroethane

[0090] Experimental example

[0091] (1) Calculation of GWP

[0092] Based on the global warming potential (GWP) of R-744, R-1234yf and R-152a contained in the mixed refrigerant composition according to the Intergovernmental Panel on Climate Change (IPCC), the global warming potential (GWP) of the mixed refrigerant composition was calculated by taking the arithmetic average according to the respective weight ratios of R-744, R-1234yf and R-152a.

[0093] The global warming potential (GWP) according to the above IPCC is based on the global warming potential (GWP) based on 100 years.

[0094] The calculated global warming potential (GWP) is shown in Table 2 below.

[0095]

Table 2

[0096] distinguish Global Warming Potential (GWP) Example 1 7.15 Example 2 13.30 Example 3 19.45 Example 4 25.6 Example 5 7.15 Example 6 13.30 Example 7 19.45 Example 8 25.60 Example 9 7.15 Example 10 13.30 Embodiment 11 19.45 Example 12 25.60 Example 13 7.15 Embodiment 14 13.30 Embodiment 15 19.45 Example 16 25.60 Embodiment 17 7.15 Embodiment 18 13.30 Embodiment 19 19.45 Embodiment 20 25.60 Embodiment 21 37.90 Comparative Example 1 1 Comparative Example 2 50.2 Comparative Example 3 37.9 Comparative Example 4 50.2 Comparative Example 5 13.3 Comparative Example 6 37.9

[0097] (2) Refrigeration evaluation

[0098] Figure 1 and Figure 2 2 are schematic diagrams respectively illustrating flows of a mixed refrigerant for heat exchange in a cooling mode or a heating mode of a heat exchanger according to exemplary embodiments.

[0099] exist Figure 1 and Figure 2 In the diagram, the direction of the arrows is used to indicate the flow of the mixed refrigerant.

[0100] See also Figure 1 In the cooling mode, the mixed refrigerant is compressed by the compressor, bypasses the internal condenser (Condenser) and the expansion valve (heating) in turn, expands in the expansion valve (cooling) after releasing heat in the external condenser, and reabsorbs heat through the evaporator.

[0101] See also Figure 2 In heating mode, the mixed refrigerant is compressed by the compressor, releases heat in the internal condenser, expands in the expansion valve (heating), absorbs heat in the external condenser, and then further absorbs heat through the chiller.

[0102] Using the refrigerant combinations of Examples 1 to 21 and Comparative Examples 1 to 6, cooling evaluation and heating evaluation were performed by the heat exchanger at different outside air temperatures.

[0103] The cooling evaluation was performed with the outside air temperature set to 45° C., and the heating evaluation was performed with the outside air temperature set to −7° C. and −20° C. The conditions of the cooling evaluation and the heating evaluation according to the above embodiment and comparative example are shown in Table 3 below.

[0104] Specifically, the outside air temperature (° C.), the condenser outlet refrigerant temperature, the condenser outlet refrigerant subcooling, the evaporator outlet refrigerant temperature, and the evaporator outlet refrigerant superheating are shown in Table 3 below.

[0105]

Table 3

[0106]

[0107]

[0108] The cooling and heating interpretations of the embodiments and comparative examples in Table 3 were verified by the OD interpretation program Cycle-D (provided by NIST). Specifically, the volume capacity, compressor outlet temperature, and pressure were evaluated by the cooling and heating interpretations.

[0109] The above volume capacity is calculated by the following formula 1.

[0110] [Formula 1]

[0111]

[0112] The evaluation results are shown in Tables 4 to 6 below.

[0113]

Table 4

[0114]

[0115]

Table 5

[0116]

[0117]

Table 6

[0118]

[0119] Referring to Table 4, according to the embodiment of the scope of the present disclosure, the volume capacity in the refrigeration evaluation (outside air temperature is 45° C.) is 2618.9 kJ / m 3 Above, the compressor outlet temperature is below 88.4℃.

[0120] Volumetric capacity is based on the amount of energy a unit volume of refrigerant can contain. The larger the volumetric capacity, the more energy the same volume of refrigerant can move, making it a refrigerant with good air conditioning performance.

[0121] Compared with the Examples, the volume capacity of Comparative Example 1 using R-1234yf alone was reduced.

[0122] Referring to Comparative Examples 3 and 4, when the content of R-152a is above 30 wt % of the total weight of the mixed refrigerant composition, the refrigeration volume capacity shows a convergent trend, while the compressor outlet pressure and the compressor outlet temperature show an upward trend.

[0123] Referring to the comparative example, when the R-744 content increases, the compressor outlet pressure and the compressor outlet temperature show an upward trend.

[0124] Referring to Table 5, according to the embodiment of the present disclosure, the volume capacity in the heating evaluation (outside air temperature is -7°C) is 1369.8 kJ / m 3 Above, the compressor outlet temperature is below 79.9℃.

[0125] Compared with the examples, the volume capacity of Comparative Example 1 using R-1234yf alone was reduced.

[0126] Referring to Comparative Examples 3 and 4, when the content of R-152a is greater than 30 wt % of the total weight of the mixed refrigerant composition, the heating volume capacity shows a convergent trend, while the compressor outlet pressure and the compressor outlet temperature show an upward trend.

[0127] Referring to the comparative example, when the R-744 content increases, the compressor outlet pressure and the compressor outlet temperature show an upward trend.

[0128] Referring to Table 6, according to the embodiment of the present disclosure, the volume capacity in the heating evaluation (outside air temperature is -20°C) is 1060.3 kJ / m 3 Above, the compressor outlet temperature is below 64.2℃.

[0129] Compared with the Examples, the volume capacity of Comparative Example 1 using R-1234yf alone was reduced.

[0130] Referring to Comparative Examples 3 and 4, when the content of R-152a is greater than 30 wt % of the total weight of the mixed refrigerant composition, the heating volume capacity shows a convergent trend, while the compressor outlet pressure and the compressor outlet temperature show an upward trend.

[0131] Referring to the comparative example, when the R-744 content increases, the compressor outlet pressure and the compressor outlet temperature show an upward trend.

[0132] Referring to the results of Tables 5 to 7, it is preferred to use a mixed refrigerant containing R-744, R-1234yf and R-152a at the same time, rather than using R-1234yf alone. In addition, it is preferred to limit the maximum content of R-744 to 10% by weight of the total weight of the mixed refrigerant composition.

[0133] In addition, further considering that the GWP increases with increasing content of R-152a, it is preferred to limit the maximum content of R-152a to 30% by weight of the total weight of the mixed refrigerant composition.

Claims

1. A mixed refrigerant composition comprising: Carbon dioxide, 2,3,3,3-tetrafluoropropene and 1,1-difluoroethane, The content of carbon dioxide is 1 wt % to 10 wt % of the total weight of the mixed refrigerant composition. The content of 2,3,3,3-tetrafluoropropylene is 65 wt % to 95 wt % of the total weight of the mixed refrigerant composition. The content of 1,1-difluoroethane is 1 wt % to 30 wt % of the total weight of the mixed refrigerant composition. The boiling point at 1 atm is -65°C to -30°C. 2 . The mixed refrigerant composition according to claim 1 , comprising the carbon dioxide, the 2,3,3,3-tetrafluoropropylene and the 1,1-difluoroethane. 3 . The mixed refrigerant composition according to claim 1 , wherein the content of 1,1-difluoroethane is 13 to 25 wt % based on the total weight of the mixed refrigerant composition. 4 . The mixed refrigerant composition according to claim 1 , wherein the content of 1,1-difluoroethane is 18 to 23 wt % of the total weight of the mixed refrigerant composition. 5 . The mixed refrigerant composition according to claim 1 , wherein a ratio of a content of the 2,3,3,3-tetrafluoropropene to a content of the carbon dioxide is 6 to 95 in a total weight of the mixed refrigerant composition. 6 . The mixed refrigerant composition according to claim 1 , wherein a ratio of a content of the 1,1-difluoroethane to a content of the carbon dioxide is 0.5 to 30 in the total weight of the mixed refrigerant composition. 7 . The mixed refrigerant composition according to claim 1 , wherein a ratio of the content of the 2,3,3,3-tetrafluoropropene to the content of the 1,1-difluoroethane is 2 to 19 in the total weight of the mixed refrigerant composition. 8 . The mixed refrigerant composition according to claim 1 , wherein the critical temperature of the mixed refrigerant composition is 90° C. to 100° C. 9 . The mixed refrigerant composition according to claim 1 , wherein the critical pressure of the mixed refrigerant composition is 30 bar to 51 bar.

10. The mixed refrigerant composition according to claim 1, wherein the temperature gradient of the mixed refrigerant composition at a pressure of 1.5 bar is 3°C to 29°C.

11. The mixed refrigerant composition according to claim 1, wherein the temperature gradient of the mixed refrigerant composition at a pressure of 15 bar is 2°C to 23°C. 12 . The mixed refrigerant composition according to claim 1 , wherein the latent heat of the mixed refrigerant composition at −25° C. is 150 kJ / kg to 250 kJ / kg. 13 . The mixed refrigerant composition according to claim 1 , wherein the global warming potential of the mixed refrigerant composition is 1 to 40.

14. A heat pump comprising the mixed refrigerant composition according to claim 1.

Images